[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.348065][ T26] audit: type=1800 audit(1571002792.543:25): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.384378][ T26] audit: type=1800 audit(1571002792.543:26): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.407701][ T26] audit: type=1800 audit(1571002792.553:27): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.67' (ECDSA) to the list of known hosts. 2019/10/13 21:40:04 fuzzer started 2019/10/13 21:40:05 dialing manager at 10.128.0.105:40973 2019/10/13 21:40:05 syscalls: 2523 2019/10/13 21:40:05 code coverage: enabled 2019/10/13 21:40:05 comparison tracing: enabled 2019/10/13 21:40:05 extra coverage: extra coverage is not supported by the kernel 2019/10/13 21:40:05 setuid sandbox: enabled 2019/10/13 21:40:05 namespace sandbox: enabled 2019/10/13 21:40:05 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/13 21:40:05 fault injection: enabled 2019/10/13 21:40:05 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/13 21:40:05 net packet injection: enabled 2019/10/13 21:40:05 net device setup: enabled 2019/10/13 21:40:05 concurrency sanitizer: enabled syzkaller login: [ 47.165181][ T7217] ================================================================== [ 47.173321][ T7217] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 47.180847][ T7217] [ 47.183168][ T7217] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1: [ 47.190698][ T7217] __zone_watermark_ok+0x106/0x240 [ 47.195798][ T7217] get_page_from_freelist+0x629/0x2300 [ 47.201260][ T7217] __alloc_pages_nodemask+0x255/0x4d0 [ 47.206628][ T7217] page_frag_alloc+0x11e/0x2d0 [ 47.211559][ T7217] __napi_alloc_skb+0x172/0x210 [ 47.216396][ T7217] page_to_skb+0x8d/0x480 [ 47.220711][ T7217] receive_buf+0x17c7/0x30b0 [ 47.225315][ T7217] virtnet_poll+0x436/0x7d0 [ 47.229807][ T7217] net_rx_action+0x3ae/0xa50 [ 47.234818][ T7217] __do_softirq+0x115/0x33f [ 47.239308][ T7217] run_ksoftirqd+0x46/0x60 [ 47.243805][ T7217] smpboot_thread_fn+0x37d/0x4a0 [ 47.248725][ T7217] kthread+0x1d4/0x200 [ 47.252793][ T7217] ret_from_fork+0x1f/0x30 [ 47.257194][ T7217] [ 47.259510][ T7217] write to 0xffff88812fffcf58 of 8 bytes by task 7217 on cpu 0: [ 47.267124][ T7217] free_one_page+0x214/0x840 [ 47.271702][ T7217] __free_pages_ok+0x370/0x640 [ 47.276450][ T7217] free_compound_page+0x3d/0x50 [ 47.281288][ T7217] __put_compound_page+0x4e/0x70 [ 47.286210][ T7217] __put_page+0x54/0xd0 [ 47.290363][ T7217] skb_release_data+0x1ba/0x3a0 [ 47.295199][ T7217] skb_release_all+0x44/0x60 [ 47.299771][ T7217] __kfree_skb+0x1f/0x30 [ 47.304012][ T7217] tcp_recvmsg+0xf59/0x1a30 [ 47.308503][ T7217] inet_recvmsg+0xbb/0x250 [ 47.312906][ T7217] sock_recvmsg+0x92/0xb0 [ 47.317216][ T7217] sock_read_iter+0x15f/0x1e0 [ 47.321880][ T7217] new_sync_read+0x389/0x4f0 [ 47.326452][ T7217] [ 47.328769][ T7217] Reported by Kernel Concurrency Sanitizer on: [ 47.334916][ T7217] CPU: 0 PID: 7217 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.342050][ T7217] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.352098][ T7217] ================================================================== [ 47.360155][ T7217] Kernel panic - not syncing: panic_on_warn set ... [ 47.366731][ T7217] CPU: 0 PID: 7217 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 47.373884][ T7217] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.383921][ T7217] Call Trace: [ 47.387200][ T7217] dump_stack+0xf5/0x159 [ 47.391445][ T7217] panic+0x209/0x639 [ 47.395333][ T7217] ? tcp_recvmsg+0xf59/0x1a30 [ 47.400007][ T7217] ? vprintk_func+0x8d/0x140 [ 47.404675][ T7217] kcsan_report.cold+0xc/0x1b [ 47.409358][ T7217] __kcsan_setup_watchpoint+0x3ee/0x510 [ 47.414894][ T7217] __tsan_write8+0x32/0x40 [ 47.419300][ T7217] free_one_page+0x214/0x840 [ 47.423883][ T7217] __free_pages_ok+0x370/0x640 [ 47.428643][ T7217] free_compound_page+0x3d/0x50 [ 47.433480][ T7217] __put_compound_page+0x4e/0x70 [ 47.438404][ T7217] __put_page+0x54/0xd0 [ 47.442550][ T7217] skb_release_data+0x1ba/0x3a0 [ 47.447391][ T7217] skb_release_all+0x44/0x60 [ 47.451967][ T7217] __kfree_skb+0x1f/0x30 [ 47.456200][ T7217] tcp_recvmsg+0xf59/0x1a30 [ 47.460699][ T7217] ? preempt_schedule_common+0x37/0x90 [ 47.466152][ T7217] inet_recvmsg+0xbb/0x250 [ 47.470564][ T7217] ? __tsan_read8+0x2c/0x30 [ 47.475055][ T7217] ? inet_sendpage+0x100/0x100 [ 47.479803][ T7217] sock_recvmsg+0x92/0xb0 [ 47.484121][ T7217] sock_read_iter+0x15f/0x1e0 [ 47.488791][ T7217] new_sync_read+0x389/0x4f0 [ 47.493475][ T7217] __vfs_read+0xb1/0xc0 [ 47.497620][ T7217] vfs_read+0x143/0x2c0 [ 47.501766][ T7217] ksys_read+0xd5/0x1b0 [ 47.505913][ T7217] __x64_sys_read+0x4c/0x60 [ 47.510409][ T7217] do_syscall_64+0xcf/0x2f0 [ 47.514916][ T7217] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.520793][ T7217] RIP: 0033:0x47c530 [ 47.524680][ T7217] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 47.544269][ T7217] RSP: 002b:000000c4206ba7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 47.552666][ T7217] RAX: ffffffffffffffda RBX: 0000000001804a60 RCX: 000000000047c530 [ 47.560621][ T7217] RDX: 0000000000001000 RSI: 000000c420326000 RDI: 0000000000000003 [ 47.568578][ T7217] RBP: 000000c4206ba830 R08: 0000000000000000 R09: 0000000000000000 [ 47.577142][ T7217] R10: 0000000000000000 R11: 0000000000000212 R12: 00000000000000a0 [ 47.585098][ T7217] R13: 00000000000000ff R14: 00007f4889d51000 R15: 0000000000000004 [ 48.723653][ T7217] Shutting down cpus with NMI [ 48.729902][ T7217] Kernel Offset: disabled [ 48.734261][ T7217] Rebooting in 86400 seconds..